CH2M Hill Singapore appointed as design consultant for Tuas Water Reclamation Plant in DTSS Phase 2

PUB, Singapore's national water agency, has appointed CH2M Hill Singapore Pte Ltd as the Detailed Design Consultant for the Tuas Water Reclamation Plant, a key component of the Deep Tunnel Sewerage System (DTSS) Phase 2.

A superhighway for used water management, the DTSS is a core water infrastructure which provides a cost-effective and sustainable solution to support Singapore’s continued growth and meet its long-term needs for used water collection, treatment, reclamation and disposal. The DTSS uses deep tunnel sewers to convey used water entirely by gravity to centralised WRPs located at the coastal areas. The used water is then treated and further purified into ultra-clean, high-grade reclaimed water called NEWater, with excess treated effluent discharged to the sea.

The used water is treated and purified into ultra-clean, high-grade reclaimed water called NEWater, with excess treated effluent discharged to the sea

DTSS Phase 1, comprising the North and Spur Tunnels, the associated link sewers, the Changi WRP and outfall, was completed in 2008. A NEWater factory, located on the rooftop of the Changi WRP, was built in 2010 to facilitate large-scale water recycling.

Expected to complete by 2025, DTSS Phase 2 will extend the deep tunnel system to cover the western part of Singapore, including the downtown area and major upcoming developments such as Tengah Town. Under DTSS Phase 2, a NEWater factory to be integrated with the Tuas WRP will be built to facilitate water recycling, contributing to the goal of increasing NEWater supply from 40% to up to 55% of total water demand in the long term.

Tuas WRP will also be co-located with NEA’s Integrated Waste Management Facility (IWMF), to harness potential synergies. The completed DTSS will also streamline the  used water network with three centralised collection and treatment points: Changi WRP in the east, Kranji WRP in the north and Tuas WRP in the west. Once Phase 2 is in place, the existing conventional WRPs at Ulu Pandan and Jurong, as well as intermediate pumping stations, will be progressively phased out and the land freed up for higher value development.

The implementation of the entire DTSS will result in a 50% reduction in land taken up by used water infrastructure once it is fully completed.

The implementation of the entire DTSS will result in a 50% reduction in land taken up by used water infrastructure once it is fully completed

CH2M Hill Singapore was appointed for DTSS Phase 2 following a pre-qualification and tender exercise in 2016. Over the next two years, the firm will develop the detailed design of Tuas WRP and subsequently supervise the construction and commissioning of the plant. The construction of Tuas WRP is expected to start in late 2018 and will feature multiple construction tenders for civil, mechanical and electrical engineering works as well as equipment providers for various plant components.

Unlike conventional WRPs, the advanced Tuas WRP will be receiving used water flows from the western part of Singapore via two separate deep tunnels a tunnel to convey domestic used water and another to convey high-strength industrial used water. It will also use membrane bioreactor (MBR) technology to treat both used water sources and to higher standards. Domestic used water will be treated at a 650,000m3/day (or 143 million imperial gallons per day) module and then further purified to NEWater, while industrial used water will be treated at a separate 150,000m3/day (or 33 million imperial gallons per day) module and sent back to industries for reuse.

With an initial total treatment capacity of 800,000m3/day (176 million imperial gallons per day or 320 Olympic-size pools), Tuas WRP will be one of the largest MBR facilities in the world, but with a 30% more compact footprint compared to conventional plants.

Tuas WRP will also feature an integrated NEWater factory, with an initial capacity of 25 million imperial gallons per day. Furthermore, Tuas WRP will be co-located with an incineration facility to harness the potential synergies of the water-energy-waste nexus, making it more efficient and greener.

'DTSS Phase 2 continues to leverage advanced technologies and detailed planning to enhance Singapore’s used water management system and ensure water resilience and sustainability for generations to come. With a separate network for the collection and treatment of industrial used water, the Tuas WRP enables PUB to not only meet the growing water needs of the industrial sector, but also ensures the continued reliability of NEWater.' said Mr Yong Wei Hin, Director, DTSS Phase 2, PUB.

Share this page